Determining the size and demographics of a television viewing audience helps television program producers improve their television programming and determine a price to be charged for advertising that is broadcasted during such programming In addition, accurate television viewing demographics allows advertisers to target audiences of a desired size and/or audiences comprised of members having a set of common, desired characteristics (e.g., income level, lifestyles, interests, etc.).
In order to collect these demographics, an audience measurement company may enlist a number of television viewers to cooperate in an audience measurement study for a predefined length of time. The viewing habits of these enlisted viewers, as well as demographic data about these enlisted viewers, are collected using automated and/or manual collection methods. The collected data is subsequently used to generate a variety of informational statistics related to television viewing audiences including, for example, audience sizes, audience demographics, audience preferences, the total number of hours of television viewing per household and/or per region, etc. monitored. For example, homes that receive cable television signals and/or satellite television signals typically include a set top box (STB) to receive television signals from a cable and/or satellite television provider. Television systems configured in this manner are typically monitored using hardware, firmware, and/or software to interface with the STB to extract or to generate signal information therefrom. Such hardware, firmware, and/or software may be adapted to perform a variety of monitoring tasks including, for example, detecting the channel tuning status of a tuning device disposed in the STB, extracting program identification codes embedded in television signals received at the STB, generating signatures characteristic of television signals received at the STB, etc. However, many television systems that include an STB are configured such that the STB may be powered independent of the television set. As a result, the STB may be turned on (i.e., powered up) and continue to supply television signals to the television set even when the television set is turned off. Thus, monitoring of television systems having independently powered devices typically involves an additional device or method to determine the operational status of the television set to ensure that the collected data reflects information about television signals that were merely supplied to the television set, which may or may not be turned on. Although there are a variety of techniques to determine the operational status of the television set, many of these techniques are invasive to the television set and increases unnecessary risk in damaging the television set during installation of the circuitry to determine the operational status. Further some of these techniques involve monitoring the consumption of power by the television set. Unfortunately, the consumption of power by the television set does not necessarily indicate that the television screen is operational. Other techniques to determine the operational status of the television set are complex and tend to be costly to implement.